<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title></title>
</head>
<body>
    <h1>这是第五个页面</h1>
    <button>后退</button>
</body>
<script>
   document.querySelector('button')
            .addEventListener('click',function(){
                history.back()
            })
</script>
</html>